T cells and antigen Pt3 (L6)

Question 1

What do T cells express

Answer 1

a T cell receptor

Question 2

What is the T cell receptor shape similar to

Answer 2

Antibody

Question 3

What is the structure of the T cell receptor

Answer 3

alpha and beta chain with hyper variable regions

Question 4

Which cell B or T has more diversity

Answer 4

T cells

Question 5

T-cells attach invaders in which part of cell

Answer 5

inside

Question 6

MHC 2 molecules show the ____

Answer 6

external world

Question 7

MHC 1 molecules show the____

Answer 7

Inside world

Question 8

How do B cells recognize antigen

Answer 8

in its native form

Question 9

How do T cells recognize antigen

Answer 9

they require antigen presenting cells

Question 10

APC=

Answer 10

antigen presenting cell

Question 11

What do CD8+ cells do

Answer 11

kill infected cells

Question 12

What do CD4+ cells do

Answer 12

help B cells

Question 13

Which cells detect MHC 1 molecules

Answer 13

CD8+ cytotoxic T cells

Question 14

2 types of T cell

Answer 14

CD8+

CD4+

Question 15

which cells detect MHC 2 molecules

Answer 15

CD4+ helper T cells

Question 16

MHC 1 cells are loaded with proteins from

Answer 16

within the cell

Question 17

What cells are MHC molecules expressed on

Answer 17

all nucleated cells (not RBC)

Question 18

which part of the T cell receptors recognizes MHC-peptide complex

Answer 18

the varible region loops

Question 19

How are the peptides formed in MHC 1

Answer 19

from defective ribosomal products and old proteins which get cut up

Question 20

How is the MHC1 peptide complex formed

Answer 20

MHC is assembled in the endoplasmic reticulum
TAP protein transports peptides into the endoplasmic reticulum where they combine with MHC
This is then exported to the cell membrane

Question 21

What happens if a virus has adapted not to express MHC 1 molecules

Answer 21

NK cells can sense if MHC is not expressed and kill cell

Question 22

Difference of MHC 2 shape

Answer 22

MHC has 2 proteins rather than 1,

open end so more flexibility in the length of peptide

Question 23

What is the length difference in MHC 2 peptides

Answer 23

MHC 2 binds longer peptides than class one

Question 24

Where do MHC 2 molecules load peptide

Answer 24

in vesicles

Question 25

Why can't MHC 2 bind peptide in ER

Answer 25

invarient chain binds instead which is degraded and leaves single CLIP peptide

Question 26

How is the single CLIP peptide removed from MHC

Answer 26

by HLA-DM protein

Question 27

What type of cells express MHC class 2

Answer 27

Dendritic cells B cells macrophages

Question 28

In dendritic cells how is the antigen loaded in MHC class 2

Answer 28

pathogen is phagocytised and pathogen peptide loaded into MHC2 molecule --> transported to cell surface

Question 29

In B cells how is the antigen loaded into MHC 2

Answer 29

antigen bound by B-cell surface receptor, antigen internalized and degraded fragments----> bound to MHC transported to cell surface

Question 30

MHC class 2 are expressed on

Answer 30

Professional antigen presenting cells

Question 31

Where do T cells undergo an education

Answer 31

the Thymus

Question 32

Where are early T cell precursors developed

Answer 32

bone marrow

Question 33

Where do T cells develop

Answer 33

thymus

Question 34

What selection do T cells undergo first

Answer 34

positive selection

Question 35

What is positive selection

Answer 35

generating a repertoire of T cells that have the best chance of responding

Question 36

What is negative selection

Answer 36

T cells are destroyed if they respond to self peptides in MHC molecules

Question 37

MHC=

Answer 37

major histocompatibility complex

Question 38

What gene has the most polymorphism

Answer 38

MHC